1. Field of the Invention
The present invention relates to a cassette for storing a strip member and a recording apparatus using the aforesaid cassette. More particularly, the present invention relates to a cassette having a control member for controlling the rotation of a winding member to wind a strip member, and a recording apparatus using the aforesaid cassette.
2. Related Background Art
The strip ink sheet used for a thermal transfer printer is extremely thin, so that the strip ink sheet has been cassetted in many cases for its easy handling in recent years, and in general, a brake mechanism is provided in the cassette in order to prevent the supply reel and rewinding reel, which are stored therein, from running idle.
In the conventional cassette, the supply reel 52 with the ink sheet 51, which is a strip member, wound around the reel and the rewinding reel 53 are rotatively stored in a case 50 as shown in FIG. 1, and on one side end in the axial direction of each of the reels 52 and 53, a V shaped groove 54 is formed in the radial direction each at an angle of 90.degree. as shown in FIG. 2A. In the inner face of the case 50 facing this end, a V shaped projection 55 as shown in FIG. 2B is formed. Then, the supply reel 52 and rewinding reel 53 are pressed toward the V shaped projections 55 of the case 50 by the compression of flat springs 56 and others to allow the aforesaid V shaped grooves 54 and V shaped projections 55 to be fitted for stoppage.
In the aforesaid cassette, the rotation of the reels 52 and 53 is regulated by the V shaped projections 55 of the case 50 which are fitted into the V shaped grooves 54 of the reels 52 and 53 so as not to allow them to run idle. Then, the structure is arranged so that when the aforesaid cassette is installed into the recording apparatus, the reel driving shafts which are not shown in FIG. 1 are coupled to the supply reel 52 and rewinding reel 53 and at the same time, the reels 52 and 53 are pressed in the direction indicated by arrow x in FIG. 1 to release the fitting of the aforesaid V shaped grooves 54 and V shaped projections 55.
However, in the structure wherein the rotation of the reels 52 and 53 is regulated by the fitting of the aforesaid V shaped grooves 54 and V shaped projections 55, the V shaped grooves 54 on the reels 52 and 53 are provided each at an angle of 90.degree. in the radial direction. Therefore, when the cassette is removed from the recording apparatus, each of the reels 52 and 53 is rotated maximum 90.degree. if the aforesaid V shaped grooves 54 and V shaped projection 55 are not fitted at that time. As a result, the ink sheet 51 is caused to slack in an amount equivalent to 180.degree. as a whole. This slacking can be reduced by increasing the numbers of the V shaped grooves 54, but its complete elimination is impossible.
Also, in the case where an irregularity of rewinding occurs or expansion of the ink sheet 51 occurs in use, the slacking of the ink sheet 51 is still generated at the time of its removal from the recording apparatus in a state that the V shaped grooves 54 and V shaped projections 55 are fitted exactly even if the slacking of the ink sheet 51 between the reels 52 and 53 is completely removed before the aforesaid cassette is installed into the recording apparatus. Then, there is a possibility that the ink sheet 51 is wrinkled by a shock when the fitting of the V shaped grooves 54 and V shaped projections 55 is once released to rotate the reels 52 and 53 to remove the aforesaid slacking and the V shaped grooves 54 and V shaped projections 55 are again fitted subsequent thereto.
As for another structure of the conventional cassette, there is a structure such as shown in FIG. 3 wherein the ink sheet 150 is wound around the supply reel 151 and rewinding reel 152, and the reels 151 and 152 are supported by the reel receiving portion 153a in the lower case 153 and the reel receiving portion 154a in the upper case 154. At the same time, springs 155 are sandwiched to give tension to the reels 151 and 152 in the axial direction, and the upper and lower cases 153 and 154 are welded or fixed by machine screws or the like.
However, the aforesaid cassette needs many numbers of parts as compared with its simple structure, and it takes more time in assembling the cassette because a process is needed to couple the upper and lower cases 153 and 154, leading to an increase in its manufacturing cost.
Also, as to the brake mechanism for the cassette storing a cassette tape and the like, there is disclosed a brake mechanism in Japanese Utility Model Laid-Open Application No. 57-168891, Japanese Utility Model Laid-Open Application No. 57-180890, and others, wherein a pair of reels each having teeth on the periphery of its flange are incorporated in the case, and the braking nails are caused to fit into the aforesaid teeth respectively. However, there are problems that not only the numbers of the parts are great, but the structure is also complicated.